This book is designed primarily to meet two objectives. It is intended to serve as a text book of a one semester university course for graduate or senior undergraduate students in the physical sciences, electrical engineering and other related disciplines or it may be used as a reference book for those who are working in the field. For those intending to use the book for self-study, a general knowledge of electromagnetism, electrical circuitry and plasma and discharge physics is necessary. The contents are arranged so that theory and practice are balanced and each topic shall consist of essentially four basic elements: fundamental principles, mathematical expressions and formulas, examples and illustrations, numerical data and applications. Lengthy theoretical discussions and detailed mathematical derivations are avoided whenever possible.